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1.
《Pancreatology》2022,22(7):880-886
BackgroundPremature intracellular trypsinogen activation has long been considered a key initiator of acute pancreatitis (AP). Cathepsin B (CTSB) activates trypsinogen, while cathepsin L (CTSL) inactivates trypsin(ogen), and both proteins play a role in the onset of AP.MethodsAP was induced by 7 hourly intraperitoneal injections of cerulein (50 μg/kg) in wild-type and pancreas-specific conditional Ctsb knockout (CtsbΔpan), Ctsl knockout (CtslΔpan), and Ctsb;Ctsl double-knockout (CtsbΔpan;CtslΔpan) mice. Pancreatic samples were collected and analyzed by histology, immunohistochemistry, real-time PCR, and immunoblots. Trypsin activity was measured in pancreatic homogenates. Peripheral blood was collected, and serum amylase activity was measured.ResultsDouble deletion of Ctsb and Cstl did not affect pancreatic development or mouse growth. After 7 times cerulein injections, double Ctsb and Ctsl deficiency in mouse pancreases increased trypsin activity to the same extent as that in Ctsl-deficient mice, while Ctsb deficiency decreased trypsin activity but did not affect the severity of AP. CtsbΔpan;CtslΔpan mice had comparable serum amylase activity and histopathological changes and displayed similar levels of proinflammatory cytokines, apoptosis, and autophagy activity compared with wild-type, CtsbΔpan, and CtslΔpan mice.ConclusionDouble deletion of Ctsb and Ctsl in the mouse pancreas altered intrapancreatic trypsin activity but did not affect disease severity and inflammatory response after cerulein-induced AP. 相似文献
2.
《Vaccine》2022,40(30):4038-4045
PurposeAs protection from COVID-19 following two doses of the BNT162b2 vaccine showed a time dependent waning, a third (booster) dose was administrated. This study aims to compare the antibody response following the third dose versus the second and to evaluate post-booster seroconversion.MethodsA prospective observational study conducted in Maccabi Healthcare Services. Serial SARS-CoV-2 Spike IgG tests, 1,2,3 and 6 months following the second vaccine dose and one month following the third were obtained. Neutralizing antibody levels were measured in a subset of participants. Per individual SARS-CoV-2 Spike IgG titer ratios were calculated one month after the booster administration compared to titers one month following the second dose and prior to booster.ResultsAmong 110 participants, 56 (51%) were women. Mean age was 61.7 ± 1.9 years and 66 (60%) were immunocompromised. One month after third dose, IgG titers were induced 7.83 (95 %CI 5.25–11.67) folds and 2.40 (95 %CI 1.90–3.03) folds compared to one month after the second, in the immunocompromised and immunocompetent groups, respectively. Of the 17 immunocompromised participants who were seronegative after the second dose, 4 (24%) became seropositive following the third. Comparing the titers prior to the third dose, an increase of 50.7 (95 %CI 32.5–79.1) fold in the immunocompromised group and 25.7 (95 %CI 19.1–34.7) fold in and immunocompetent group, was observed.ConclusionA third BNT162b2 vaccine elicited robust humoral response, superior to the response observed following the second, among immunocompetent and immunocompromised individuals. 相似文献
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地鳖中的纤溶活性蛋白是从地鳖中提取的具有抗栓及抗肿瘤作用的有效成分,其口服易被上消化道酶分解从而限制了应用。采用恒流泵滴制法开发地鳖纤溶活性蛋白时间/pH依赖口服结肠靶向微囊(EnpolypHaga fibrinolytic protein oral colon targeting microcapsules, CTM-EFP)。采用单因素实验和正交实验相结合的方法寻找到包封率为60.17 % ± 2.72 %、载药量为15.50 % ± 0.44 % 的最佳配方。扫描电子显微镜(SEM)显示微囊呈球形、表面光滑,在人工肠液中24 h的累积释放度为99.53 % ± 0.69 %,在人工胃液中24 h累积释放度为7.43 ± 1.04 %,通过时间/pH依赖达到结肠靶向作用。CTM-EFP在人工肠液中的体外释放曲线符合Korsmeyer方程,提示地鳖纤溶活性蛋白(EnpolypHaga fibrinolytic protein, EFP)是通过扩散和侵蚀机制结合释放的。CTM-EFP为EFP的口服给药提供了一种新的剂型,为EFP应用于临床提供参考。 相似文献
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《Survey of ophthalmology》2023,68(5):940-956
Congenital aniridia is a panocular disorder that is typically characterized by iris hypoplasia and aniridia-associated keratopathy (AAK). AAK results in the progressive loss of corneal transparency and thereby loss of vision. Currently, there is no approved therapy to delay or prevent its progression, and clinical management is challenging because of phenotypic variability and high risk of complications after interventions; however, new insights into the molecular pathogenesis of AAK may help improve its management. Here, we review the current understanding about the pathogenesis and management of AAK. We highlight the biological mechanisms involved in AAK development with the aim to develop future treatment options, including surgical, pharmacological, cell therapies, and gene therapies. 相似文献
8.
目的 测定儿童1型糖尿病(T1DM)患者骨密度(BMD),分析探讨骨密度变化的影响因素。方法 选取于2018年1月—2021年6月于我院收治的儿童1型糖尿病患者76例,收集性别、年龄、发病年龄、身高、体重、BMI、病程等基本资料,检测空腹血糖、空腹C肽、糖化血红蛋白(HbA1c)、血碳酸氢根(HCO3-)、血清碱性磷酸酶(ALP),应用双能X线吸收测定法测定骨密度,获取Z值。结果 76例儿童1型糖尿病患者骨密度Z值为-0.93±2.14。HbA1c、病程与骨密度Z值呈负相关,差异具有统计学意义(分别B=-0.334,P<0.001;B=-0.191,P=0.017)。结论 儿童1型糖尿病患者骨密度低于健康儿童,血糖控制不良、病程长是1型糖尿病儿童骨密度减低的危险因素。 相似文献
9.
目的:分析SAA、hs-CRP、IL-6联合检测在儿童感染性疾病中的诊断价值。方法:选择2019年1月~2020年10月某院收治的72例感染性疾病患儿开展研究,根据患儿的病原体检测结果划分为病毒感染组和细菌感染组各36例,另选择同期体检的36名健康儿童作为研究的参照组,分别比较3组的SAA、hs-CRP、IL-6等指标水平的差异。结果:细菌感染组的SAA、hs-CRP、IL-6等指标水平及阳性率均高于病毒感染组、参照组,同时病毒感染组的SAA、hs-CRP、IL-6等指标水平及阳性率高于参照组(P<0.05);SAA、hs-CRP、IL-6联合诊断的敏感度、准确度、阳性预测值、阴性预测值均高于SAA、hs-CRP、IL-6三个指标单独检测的敏感度、准确度、阳性预测值、阴性预测值,差异有统计学意义(P<0.05);联合检测的特异度与单独检测特异度对比无统计学意义(P>0.05)。结论:SAA、hs-CRP、IL-6联合诊断在儿童感染性疾病中具备较高的诊断价值,临床可将SAA、hs-CRP、IL-6作为该病的诊断辅助指标,有效提高疾病的诊断准确性。 相似文献
10.
Guo-Quan Shi Huajun Zhu & Zhen-Guo Yan 《Communications In Computational Physics》2022,31(4):1215-1241
A priori subcell limiting approach is developed for high-order flux reconstruction/correction procedure via reconstruction (FR/CPR) methods on two-dimensional unstructured quadrilateral meshes. Firstly, a modified indicator based on
modal energy coefficients is proposed to detect troubled cells, where discontinuities
exist. Then, troubled cells are decomposed into nonuniform subcells and each subcell has one solution point. A second-order finite difference shock-capturing scheme
based on nonuniform nonlinear weighted (NNW) interpolation is constructed to perform the calculation on troubled cells while smooth cells are calculated by the CPR
method. Numerical investigations show that the proposed subcell limiting strategy on
unstructured quadrilateral meshes is robust in shock-capturing. 相似文献